Area Forecast Discussion
Issued by NWS Sterling, VA

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638 FXUS61 KLWX 161407 AFDLWX Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 1007 AM EDT Mon Oct 16 2017 .SYNOPSIS... A cold front is pushing southeast of the Mid Atlantic today. High pressure will return by tonight and hold through next weekend. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... Showers pushing off the tip of southern Maryland onto the eastern shore at this time. Additional showers depicted across south-central Virginia. These will be lifting northeast today, which will keep a chance PoP in place across the southeastern corner of the forecast area for several more hours. A few breaks in the cloud cover evident on visible satellite across the Potomac Highlands. Scattered to broken cumulus will likely persist in the cold air advection regime. It will also be breezy with gusts of 20-30 mph. Temperatures will likely keep falling through the morning, then rebound a little during the afternoon. Calendar day highs likely occurred overnight, with daytime highs in the lower to mid 60s. && .SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/... After this evening, it`s mainly a temperature forecast through the middle of the week, with attention paid to frost/freeze concerns. High pressure will move in from the west tonight and then remain directly over the region through the middle of the week. Clouds will be minimal and winds light. Have trended forecast toward colder guidance for overnight lows given what should be fairly good radiational cooling conditions. Tonight may be a little tricky since some wind is likely to linger, but it does look like calmer conditions are likely toward dawn. A Freeze Watch will be in effect for portions of the highlands tonight. Would not be surprised if there were some pockets of near- freezing temperatures in the rest of the western valleys as well. Will let the day shift determine which areas will need a Frost Advisory, with locations west of the Blue Ridge looking most favorable. Temperatures will gradually moderate through the middle of the week, but not before another potential frost/freeze for outlying areas Tuesday night. Daytime highs will remain in the 60s Tuesday, but inch into the 70s for some areas on Wednesday. && .LONG TERM /THURSDAY THROUGH SUNDAY/... High pressure is expected to dominate through the long term, resulting in dry conditions through the weekend. Temperatures will be moderating as we head through time as ridging builds aloft and southwesterly flow comes to dominate as the high slowly pushes east off the coast. We are heading deeper into autumn, with diminishing sunlight and sun angle, so the level of warmth we saw early in the month is not likely...our current level of sunshine is about the same we would get in February. However, enough warmth will build northward from the tropics to make above normal temperatures very likely late in the week and this weekend (normals now having fallen into the 60s). && .AVIATION /14Z MONDAY THROUGH FRIDAY/... Gusty NW winds of 20-25 kt will be possible during the daylight hours today, with skies trending toward scattered/broken cumulus. High pressure begins moving over the area tonight and will remain in control through the middle of the week. No aviation concerns are expected. No significant aviation concerns are expected late in the week, though patchy fog or areas of low clouds can`t be entirely ruled out during the late night and early morning hours. && .MARINE... Gusts have been sporadic this morning, but winds of 20-25 kt will be common through the day as breaks in the cloud cover become more apparent. Small Craft Advisory in place for all waters through the evening and a staggered decrease through noon Tuesday, since it looks like mixing will only slowly decrease and 20-25 kt winds aloft will remain over the warm waters of the Bay into Tuesday morning. By noontime on Tuesday, high pressure will be building overhead, and lighter winds can be expected through the middle of the week. Significant marine hazards are not anticipated to be a concern Thursday or Friday, though southerly channeling resulting in a small craft advisory can`t be entirely ruled out. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...None. MD...None. VA...Freeze Watch from late tonight through Tuesday morning for VAZ503-504. WV...Freeze Watch from late tonight through Tuesday morning for WVZ501-502-505-506. MARINE...Small Craft Advisory until 6 AM EDT Tuesday for ANZ531>533- 539>542. Small Craft Advisory until midnight EDT tonight for ANZ530-535- 536-538. Small Craft Advisory until noon EDT Tuesday for ANZ534-537-543. && $$ SYNOPSIS...RCM NEAR TERM...HTS/ADS SHORT TERM...ADS LONG TERM...RCM AVIATION...ADS/RCM MARINE...HTS/ADS/RCM is the U.S. government's official web portal to all federal, state and local government web resources and services.